DIXON performs Preliminary Maintenancel Inspection (PMI) on all tanks in order to review the coating's performance, qualify any structural damage, review OSHA standards and EPA health requirements, and to evaluate the need for cathodic protection. In order to expedite the PMI, interior surfaces of the tank are thoroughly cleaned. After the inspection is complete, the owner is made fully aware of the interior and exterior coating systems, their expected life, and any environmental concerns. If any repairs are necessary, the inspection will evaluate the cost of removal, collection, disposal and recoating, establish a recommended date of work, and itemize all repairs to the tank. DIXON will prepare a detailed report of "Conclusions and Recommendations" to be submitted to the owner regarding the noted items.

High Pressure Cleaning

DIXON recommends high pressure cleaning during the Maintenance Inspection to remove all the collected mud on the tank in order to detect any deterioration of the steel, and also to perform an accurate adhesion test on the remaining coating. A high pressure water source from a community fire truck or a portable pump will do the job. DIXON recommends using a hose with an adjustable nozzle for fog or a straight stream that has a 30 gallons per minute capacity.

After high pressure cleaning, DIXON provides a detailed report including photographs, budget estimates, and a Field Inspection Report (FIR), which informs contractors about the dimensions and conditions.

Chlorination

After the Maintenace Inspection is complete, DIXON chlorinates the tank per AWWA D652 method 3. After acceptable bacteriological results are obtained.

Environmental Concerns

The quality of the existing coating and recoatability is measured against new OSHA lead standards and containment requirements; therefore, coating samples are collected to determine possible environmental concerns. Due to the cost on particular projects, DIXON recommends the owner's engineer evaluate replacement versus repair.

General Recommendations

• Inspection Date: DIXON will arrange a date of inspection that is mutually agreeable. The tower will be out of service from the day it is drained, until chlorination and testing; approximately four days.
• Inspection Duration: DIXON performs an entire inspection within one day unless an excessive amount of mud is discovered.
• Sampling Tap: DIXON recommends installing a sampling tap if the tank does not have one.
• Pressure Relief Valves: Dixon can provide pressure relief valves to assist systems with only one tank in regulating pressures while the tank is out of service.